<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
	</body>
    <script>
        (function(){
            var _ = function (obj) {
                if (obj instanceof _) { return obj } 
                if () {}
            }
        })()
    </script>
</html>